• Recent Problems

    How many different triangles are there in the figure?
    Grades: 3rd to 5th
    Classify two-dimensional figures into categories based on their properties.

    To the left, an 8 × 8 grid can be covered by one square (measuring 8 × 8), by four squares (measuring 4 × 4 each), or by ten squares (one 5 × 5, three 3 × 3, two 2 × 2, and four 1 × 1). 

    Find all values of n for which it is impossible to cover an 8 × 8 grid with n squares of integer side length.

    Grades: 3rd to 5th
    Measurement & Data
    Geometric measurement: understand concepts of area and relate area to multiplication and to addition.
    3.MD.C.5a, 3.MD.C.5b, 3.MD.C.6
    In 2008, September and December both began on a Monday. But every year, there are two months that do not begin on the same day of the week as any other month. What are those two months?
    Write 2014 with the first four prime numbers, with the aid of the operations addition, multiplication and exponentiation.
    Grades: 6th to 8th, 3rd to 5th
    Algebraic Thinking
    Apply and extend previous understandings of arithmetic to algebraic expressions.
    Gain familiarity with factors and multiples.
    Multiply and divide within 100.
    3.OA.C.7, 4.OA.B.4, 6.EE.A.1
    If x2 + y2 = 36, xy = 32, what is the positive value of x + y?
    Grades: 9th to 12th
    Interpreting Functions
    Reasoning with Equations and Inequalities
    HSA-REI.B.4b, HSF-IF.C.8a
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